Aircraft designs often use aerodynamic struts to mount devices on an aircraft. Airflows around the aerodynamic struts may have a velocity distortion caused by a slowing of boundary layer air around the aerodynamic strut. In particular, a velocity distortion may result from aerodynamic struts preceding an open-rotor fan propulsion system in an airflow. Interaction of blades of the open rotor fan propulsion system with the velocity distortion may create turbulence and result in a non-optimal noise level.
Existing solutions generally address the velocity distortion by blowing bleed air from an aircraft engine out of a trailing edge of the aerodynamic strut. A disadvantage of the existing solutions is a requirement for a significant amount of bleed air causing a significant increase in fuel consumption of the aircraft engine. In addition, the bleed air and resulting fuel consumption performance penalty may increase design complexity of the aircraft engine. Furthermore, the bleed air may be hot and the resulting thermal distortion may create additional noise when interacting with the open-rotor fan blades. The hot engine bleed air may also complicate design (e.g., thermal design) of the open-rotor fan blades, which may impose additional weight and performance penalties on the open-rotor fan propulsion system.
Therefore, there is a need for systems and methods for reducing velocity distortion caused by an aerodynamic strut preceding an open-rotor propulsion system in an airflow.